Many electronic documentation systems in acute care settings of healthcare enterprises employ a user interface for documenting clinical information such as patient vital signs, infusions, outputs such as blood and urine flow, laboratory values, notes, images, and orders. Some of these documentation systems include the recording of alarm system events intended for real-time intervention when patients are experiencing emergencies. These emergencies often require immediate response as a matter of patient survival.
Historically, medical devices such as physiologic monitors, mechanical ventilators, etc., record live physiologic signals, such as cardiorespiratory measurements including, but not limited to, heart rate, breathing rate, and blood pressure. These devices then provide the data to documentation systems for continuous management of a patient's status.
These medical devices produce alarm signals in addition to the measurement data, and the alarm signals are intended to provide general notice, warning, and crisis-level notice to the clinicians when certain events are deemed to be of an emergent or potentially life-threatening nature. For example, identification of asystole, ventricular tachycardia or fibrillation, high peak pressure, low tidal volume, and cessation of breathing, or apnea, are events that would merit emergency intervention.
Machine-generated alarm signals are often communicated to central monitoring stations separate from the signals provided to clinical documentation systems as these monitoring stations provide for the review of real-time data intended for interventional guidance to the clinician. These central monitoring stations are intended to provide live and real-time oversight of patient physiological measurements for the express purpose of identifying current status of the patient's vital signs, especially the cardiorespiratory parameters.
Alarm signals issued by the medical devices are typically reactive in nature—meaning they are issued after an identified event occurs. Examples of such events are a threshold limit breach in a particular physiological measurement as listed as examples above. These alarm signals are often transmitted to alarm communication systems for remote notification of clinical staff when the clinicians are not immediately present at the point of care. The communication and display of alarm signals generated by medical devices are functions which will be referred to as being provided by an alarm system.
Historically, alarm systems are static in that they: (1) do not permit dynamic manipulation of alarm thresholds in real-time; (2) are limited in that they require alarm thresholds to be set by clinicians; (3) are not capable of being changed remotely; (4) do not have analytical tools to determine alarm thresholds in real time; (5) do not provide an easy and simple way to toggle between alarm thresholds; (6) do not provide the capability to alter or manipulate alarm thresholds based on the frequency of alarms; (7) do not provide the capability to create new types of alarm signals based on the characteristics of the data based on variations in observed signal behavior, nor tailor these new types of alarm signals based on characteristics of the patient; and (8) do not enable the incorporation of external or secondary information that could inform the user as to whether an alarm is actionable clinically or not. Examples of external or secondary information could include indications of the existence of signal artefacts that could invalidate measurements obtained from a sensor, such as calibration issues or sensor disconnects. This lack of flexibility frequently results in alarms being issued that are actionable, but not clinically informative from the perspective of identifying an issue with the patient, but, rather, an issue with the measurements and measuring equipment. Yet, these types of alarms result in the interruption of care when they distract providers unnecessarily, possibly diverting their attention from those patients who express with truly clinically-actionable events.
The implied lack of flexibility associated with the present family of machine-generated alarm signals can translate into a lack of skill in terms of the accuracy with which reactive medical device alarm signals can detect and discriminate between clinically-actionable indications in the patient and artefact-based signals that carry no clinical importance. This latter event is oftentimes referred to as the occurrence of false alarms.
What is needed is a method to reduce the number of false alarms. The present invention provides an approach for addressing this need.